LXR linux/fs/btrfs/ordered-data.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
   4 */
   5
   6#ifndef BTRFS_ORDERED_DATA_H
   7#define BTRFS_ORDERED_DATA_H
   8
   9/* one of these per inode */
  10struct btrfs_ordered_inode_tree {
  11        spinlock_t lock;
  12        struct rb_root tree;
  13        struct rb_node *last;
  14};
  15
  16struct btrfs_ordered_sum {
  17        /* bytenr is the start of this extent on disk */
  18        u64 bytenr;
  19
  20        /*
  21         * this is the length in bytes covered by the sums array below.
  22         */
  23        int len;
  24        struct list_head list;
  25        /* last field is a variable length array of csums */
  26        u8 sums[];
  27};
  28
  29/*
  30 * bits for the flags field:
  31 *
  32 * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
  33 * It is used to make sure metadata is inserted into the tree only once
  34 * per extent.
  35 *
  36 * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
  37 * rbtree, just before waking any waiters.  It is used to indicate the
  38 * IO is done and any metadata is inserted into the tree.
  39 */
  40enum {
  41        /* set when all the pages are written */
  42        BTRFS_ORDERED_IO_DONE,
  43        /* set when removed from the tree */
  44        BTRFS_ORDERED_COMPLETE,
  45        /* set when we want to write in place */
  46        BTRFS_ORDERED_NOCOW,
  47        /* writing a zlib compressed extent */
  48        BTRFS_ORDERED_COMPRESSED,
  49        /* set when writing to preallocated extent */
  50        BTRFS_ORDERED_PREALLOC,
  51        /* set when we're doing DIO with this extent */
  52        BTRFS_ORDERED_DIRECT,
  53        /* We had an io error when writing this out */
  54        BTRFS_ORDERED_IOERR,
  55        /*
  56         * indicates whether this ordered extent has done its due diligence in
  57         * updating the isize
  58         */
  59        BTRFS_ORDERED_UPDATED_ISIZE,
  60        /* Set when we have to truncate an extent */
  61        BTRFS_ORDERED_TRUNCATED,
  62        /* Regular IO for COW */
  63        BTRFS_ORDERED_REGULAR,
  64};
  65
  66struct btrfs_ordered_extent {
  67        /* logical offset in the file */
  68        u64 file_offset;
  69
  70        /* disk byte number */
  71        u64 start;
  72
  73        /* ram length of the extent in bytes */
  74        u64 len;
  75
  76        /* extent length on disk */
  77        u64 disk_len;
  78
  79        /* number of bytes that still need writing */
  80        u64 bytes_left;
  81
  82        /*
  83         * the end of the ordered extent which is behind it but
  84         * didn't update disk_i_size. Please see the comment of
  85         * btrfs_ordered_update_i_size();
  86         */
  87        u64 outstanding_isize;
  88
  89        /*
  90         * If we get truncated we need to adjust the file extent we enter for
  91         * this ordered extent so that we do not expose stale data.
  92         */
  93        u64 truncated_len;
  94
  95        /* flags (described above) */
  96        unsigned long flags;
  97
  98        /* compression algorithm */
  99        int compress_type;
 100
 101        /* reference count */
 102        refcount_t refs;
 103
 104        /* the inode we belong to */
 105        struct inode *inode;
 106
 107        /* list of checksums for insertion when the extent io is done */
 108        struct list_head list;
 109
 110        /* If we need to wait on this to be done */
 111        struct list_head log_list;
 112
 113        /* If the transaction needs to wait on this ordered extent */
 114        struct list_head trans_list;
 115
 116        /* used to wait for the BTRFS_ORDERED_COMPLETE bit */
 117        wait_queue_head_t wait;
 118
 119        /* our friendly rbtree entry */
 120        struct rb_node rb_node;
 121
 122        /* a per root list of all the pending ordered extents */
 123        struct list_head root_extent_list;
 124
 125        struct btrfs_work work;
 126
 127        struct completion completion;
 128        struct btrfs_work flush_work;
 129        struct list_head work_list;
 130};
 131
 132/*
 133 * calculates the total size you need to allocate for an ordered sum
 134 * structure spanning 'bytes' in the file
 135 */
 136static inline int btrfs_ordered_sum_size(struct btrfs_fs_info *fs_info,
 137                                         unsigned long bytes)
 138{
 139        int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
 140        int csum_size = btrfs_super_csum_size(fs_info->super_copy);
 141
 142        return sizeof(struct btrfs_ordered_sum) + num_sectors * csum_size;
 143}
 144
 145static inline void
 146btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
 147{
 148        spin_lock_init(&t->lock);
 149        t->tree = RB_ROOT;
 150        t->last = NULL;
 151}
 152
 153void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
 154void btrfs_remove_ordered_extent(struct inode *inode,
 155                                struct btrfs_ordered_extent *entry);
 156int btrfs_dec_test_ordered_pending(struct inode *inode,
 157                                   struct btrfs_ordered_extent **cached,
 158                                   u64 file_offset, u64 io_size, int uptodate);
 159int btrfs_dec_test_first_ordered_pending(struct inode *inode,
 160                                   struct btrfs_ordered_extent **cached,
 161                                   u64 *file_offset, u64 io_size,
 162                                   int uptodate);
 163int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 164                             u64 start, u64 len, u64 disk_len, int type);
 165int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
 166                                 u64 start, u64 len, u64 disk_len, int type);
 167int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
 168                                      u64 start, u64 len, u64 disk_len,
 169                                      int type, int compress_type);
 170void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 171                           struct btrfs_ordered_sum *sum);
 172struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
 173                                                         u64 file_offset);
 174void btrfs_start_ordered_extent(struct inode *inode,
 175                                struct btrfs_ordered_extent *entry, int wait);
 176int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
 177struct btrfs_ordered_extent *
 178btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
 179struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 180                struct btrfs_inode *inode,
 181                u64 file_offset,
 182                u64 len);
 183int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 184                                struct btrfs_ordered_extent *ordered);
 185int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 186                           u8 *sum, int len);
 187u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 188                               const u64 range_start, const u64 range_len);
 189u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 190                              const u64 range_start, const u64 range_len);
 191void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree,
 192                                        struct btrfs_inode *inode, u64 start,
 193                                        u64 end,
 194                                        struct extent_state **cached_state);
 195int __init ordered_data_init(void);
 196void __cold ordered_data_exit(void);
 197
 198#endif
 199